This invention relates to decorative plaques and emblems and methods of making them, and more particularly to a decorative emblem or plaque having a decorative surface encapsulated in a cured plastic resin integral with a bezel and a method for making the same.
Decorative plaques and emblems are widely used throughout a number of industries including the automotive and appliance industries. In the past, such plaques and emblems were formed by flowing a colored vitreous frit into a bronze substrate and firing it at 1250.degree. F. The glass-like vitreous enamel served to beautify the product and protect the decorative emblem from weathering. Today, plastics are primarily used for making such plaques and emblems. For example, the assignee of the present invention has been producing emblems since 1966 which have a molded or cast body into which plastic is deposited. A description of such products can be found in the July-August, 1972, issue of duPont Magazine, pp. 29-31.
Likewise, Loew, U.S. Pat. No. 3,654,062, discloses a process for injection molding a decorative Mylar facing sheet over a vinyl plastic body. The plaque is coated with a layer of protective varnish on the outer surface of the facing sheet. Gits, U.S. Pat. No. 3,246,066, is similar in that male and female molds are used to form a cavity into which a decorative foil is placed and into which a clear plastic material is injected. Prior to injecting a clear plastic material against the front face of the foil, the foil is precoated. Other molding processes such as compression molding are also known in the art. See for example U.S. Pat. Nos. 2,244,565; 2,931,119; 3,075,249; and 3,114,597.
Also known generally is the concept of encapsulating an article in plastic by casting, partially curing, inserting the article, casting again, and completing the cure. For example, in Brody, U.S. Pat. No. 3,660,211, the article is a metal foil of a multicolored iridescent body embedded between two layers of a polyester resin; in Smith, U.S. Pat. No. 3,312,197, the article is a facsimile of a coin embedded between a transparent and an opaque, colored plastic resin material; and in Miori, U.S. Pat. No. 4,067,947, the article is embedded between two different layers of plastic resin material.
In Waugh, U.S. Pat. No. 4,100,010, assigned to the assignee of this invention, there is disclosed an improved process of producing decorative emblems. That process involves casting a plastic material onto decorative foil shapes to form a meniscus which when cured gives a lens effect to the top surface of the foil. A problem with that process is that the then capped substrate will be used as an insert to be placed inside a decorative bezel, which is typically a highly polished die casting, plastic, metallized plastic, or some other decorative material. See also U.S. Pat. Nos. 4,087,570 and 4,139,654.
Therefore, in order to produce a complete emblem, it is necessary to decorate the foil substrate, emboss the decorated substrate, apply a pressure-sensitive adhesive to the back of the substrate, cast the plastic material onto the top surface of the substrate, cure the plastic, and then insert the capped decorated substrate into a separately manufactured bezel. As can be seen, such a process involves a large number of process steps, many of which require skilled craftsman and accompanying high labor costs.
Attempts have also been made to manufacture decorative plaques and emblems by applying a pressure-sensitive adhesive to the back of a decorated foil substrate and inserting it into a bezel. Plastic is then cast into the recess in the bezel, completely covering the substrate. However, the above method suffers from the problem of gas bubble formation in the plastic during curing caused by the release of gas bubbles from volatile solvents present in the adhesive layer between the foil substrate and the base of the bezel during curing. The gas bubbles adversely affect the clarity and quality of the plastic layer overlying the substrate.
As can be seen, the need still exists in this art for a more efficient, reliable, and simple method of forming a decorative plaque or emblem.